Friction shock absorber



Oct 2, 1945. w. A. GEIGER 2,386,167.

FRICTION SHOCK ABSORBER Filed Jan. 6, 1944 2 Sheets-Sheet l Oct. 2, 1945 w. A. GEIGER w 2,386,107

FRICTION SHOCK ABSORBER Filgd Jan. 6, 1944 2 Sheets-Sheet 2 PatentedOct. 2, 1945 FRICTION s ooK ABSORBER I William P. Sidley, M.- F. Back,Albert P. Withall, Edwin 0. Austin, and George A.

WilliamfA. Geiger; Chicago, 111., assignor to Johnson, all of Chicago,Ill., and Alice T. Miner,

Chazy, N. Y., as trustees of Miner Foundation Ap mamn January 6, 1944,Serial No. 517,177

' 4 Claims.

This invention relates to improvements in friction shock absorbers foruse in connection with truck springs of railway cars for snubbing ordampening the action of the springs.

One of the objects of the invention is toprovide a friction shockabsorber to be substituted for one or more of the spring units of acluster of truck springs of a railway car to dampen the action of thetruck springs. r Another object is to provide a friction shock absorberof this character in'which a friction post and a pair of friction shoemembers have relative sliding frictional'engagement, and a base TheWilliam H.

railway ear.

member upon'which the shoemembers rock un der the influence of springmeans to press the shoes and post into tightfrictional engagement witheach-other. V a 1 a A more specific object is to improve the shockabsorber of this type by the provision of a fulcrum plate or base memberupon which the friction shoes are mounted to rock-With greaterfreedomunder spring pressure and thereby more effectively developfrictional engagement'with the tapered post. H

Otherobjects of the invention will appear from the following descriptionand claims in connection with the accompanying drawings which illustrateone embodiment of the invention.

Referring to the drawings, 1 i.

Fig. 1 is a transverse, vertical, sectional view of a friction shockabsorber embodying the invention; l 4

Fig. 2 is a view similar to Fig. 1 but with-the parts, with theexception of the spring,flbeing shown in full and atright angles totheirposi tion in Fig. 1; l

Figs. 3 and 4 are horizontal sectional views on the lines 3-3 and 44respectively-of Fig. l, the spring resistance being omitted from Fig. 4;

Fig. 5 is'a side view of one of the friction shoes and its horizontalplatform member; l

Fig. 6 is a top plan View thereof; a Fig. 7 is a similar top plan viewof the other shoe and its platform member;

Fig.8 is a' plan'view of the'fulcrum base or plate member; and g Fig. 9is a detail section of the upper portion of the shoes and the postmember showing a modified limit stop device. As shown in the drawings,my improved shock absorber comprisesbroadly a friction friction shoes Eand C, spring resistance D, and a baseor ful'crum plate E. i

The frictionjpost A comprises a relatively wide proper, having alaterally projecting; annular flange 2 at the upper end, which is intheform of a heavy disc having a downwardly offsetcentral portion 3which is formed with azcentral.

depression or recess 4 adapted to accommodate the usual spring-centeringprojection onthetop spring plate for the truck spring clustenof the The"post Imember proper, .which depends from the disc-like portionil,is.-tape'red downwardly (Fig. 1), thus presenting: fiatufrica tionsurfaces 6 on opposite sides thereof which converge towards each otherin downwarddi rection. At itsbottom end, thepost has laterally outwardlyprojecting heavy flanges I at the friction sides thereof, forming ineffect a head member which presents upwardly'facing, horizontal Thebottom fulcrum plate ortbasemembenE is a disc-like member substantiallyas'large in diameter as the spring resistance D and the upper headmembers, and having a flat bottom face 9 to provide a flat solidsupport'for the .device. This plate has an upstanding central boss Illon its upper side which provides for a central socket or recess II toaccommodatethe usual spring centering projection of the truck spring.plate; The upper face l2 of thefulcrum plate isbevg eled downwardly inopposite'directions from the boss ID to provide freedom of rockingmovement of the shoe members as will hereinafter appear.

The boss ll! iscut away on two sides to form vertical parallel facesl3which are spaced apart substantially the diameter of the recess II,and.

The webs l1 and I8 of therespectiveshoesfB and C are, as shown moreclearly in Figs. 2 and l, spaced apart Wider thanthevertical faces l3 ofHowever the webs l8 ofshoe Q are farther apart than the web I! ofvshoeB,so that the webs of shoe B pass between the webs ;-of shoe 0, this beingfor (the purpose :of enabling the platform segments to be positioned,ionthe opposite side of the center postAon iwhichatheir stop shoulders8. r f

for the spring resistance D. Y

' the boss I0.

60 post A ,-two

platelike portion I, which forms the post member respective frictionshoe members 1 l6: are ;posishoulders which serve to prevent lateraldisplacement or shifting of the shoe mechanism with respect to thefulcrum plate.

The webs l1 and I8 are sufficiently wide and thick to provide thenecessary strength and their lower edges extend below the planes of thesegments l and are rounded on arcs of suitable radius, as indicated by(Fig. 5) to bear upon and rock in the fulcrum channels M of the fulcrumplate E. As a matter of facility in holding the shoes and fulcrum platein assembled relation while the post and spring parts are being handledand assembled, the webs l1 and Hand the boss ID are provided with holes21 and 22 which are in substantial alignment when the parts are inposition and which are intended to receive a suitable rivet 23. Theholes provide sufficient clearance around the rivet so that the rivetdoes not act as a pivot when the webs of the shoes rock in theirbearings on the fulcrum plate.

The friction portions 16 are provided with lat eral enlargements ontheir inner sides which form the friction faces 24 for engagement withthe faces 6 of the post, and also form downwardly facing horizontalshoulders "SB-which overhang the corresponding stop flange l of the postand cooperate with the shoulders 8 to form limit stops to thelongitudinal movement of the post. The outer sides of the frictionportions ofthe shoes are preferablyrounded off, as shown, and upwardlytapered to provide proper clearance to facilitate assembly of the partswithin the spring coil.

The spring resistanceD is in the form of a single coil surrounding thepost A and the upstanding friction portions and the webs of the shoes Band C. The upper and lower ends of the spring bear respectively on theflanges of the post A and the segmental platforms of the shoes. In Fig.9, modified form of interlock between the post and the friction portionsof the shoes is shown. The flanges are eliminated on the inner end ofthe post and instead the post A is provided with a transverse hole 25 inwhich is inserted a tubular cross member 26. Vertical slots 21 areprovided in the friction shoe portions l6 which form shoulders 28 attheir upper ends against which the tubular cross piece 26 engages tolimit the lengthwise separation, of the shoes and post. The tubularcross piece is preferably in the form-of a split tube which can becontracted for insertion in the hole 25 and then expanded by its ownresilience. A bead 29 is provided in the hole before engagement with thecorresponding annular groove in the split tube to hold the tube againstdisplacementendwise of itself. In this structure, the post and the upperhead member may be made in two pieces instead of integral, and joinedtogether by riveting or welding, as indicated at 30.

In assembling the parts of my improved shock absorber, the shoes B and Care assembled by passing the webs of shoe B between the webs of shoe 0until the holes 2| of the web-s are in alignment. The rounded fulcrumends 20 of the webs are then placed in the fulcrum channels I4 and theholes 2| aligned with the-hole 22 in the boss. The rivet is theninserted and headed over to hold these three elements in position. Afterthese parts are thus assembled, the spring resistance D is placed inposition on the segmental platforms of the shoes and the shoe frictionportions spread apart sufficiently to admit betweenthem the flanges I ofthe post which is tioned. The vertical faces 13 of the boss forminserted downwardly until the flanges pass be low the shoulders 8. It isnecessary to apply some force to the post which acts to compress thespring. Upon the shoulders 8 engaging the flanges 33, the parts becomelocked together.

' The operation of the structure is as follows:

' Upon the cluster of springs of the railway car truck being compressedbetween the spring follower plates of the truck sections, the frictionpost A and. the friction shoes B and C are moved toward each other inlengthwise direction against the resistance of the spring D. Due to thetaper of the post, the cooperating ends of the shoes are spread apartand the shoes tilted on the fulcrum bearings of the webs in the bearingchannels 14. 'The increased pressure of the spring, however, upon theplatform se increases the pressure of the friction shoe portions againstthe post and enerates a high frictional resistance, thereby snubbing theaction of the truck springs. .Upon the spring follower plates beingmoved apart during recoil of the truck springs, the expansive action ofthe spring D restores all of the parts to the normal released positionshown in Fig. 1, the separation of the post and shoes being limited bythe stop flanges 33 and shoulders 8.

I claim:

1. In a friction shock absorber, the combination of a tapered frictionpost, friction shoes embracing said post on opposite sides thereof, saidshoes having laterally outwardly projecting platform members extendingtoward and beyond the opposite shoes and adapted for rocking movement,said shoes and postbeing movable lengthwise with respect to each other,spring means opposing said relative longitudinal movement of said shoesand post, said spring means bearing on said platform members to rock theshoes toward the post, said platform members having rounded bearingportions below the planes thereof, and a fulcrum plate positionedbeneath the platform members and having bearing channels for supportingthe rounded bearing portions of said platform members for rockingmovement.

2. In a friction shock absorber, the combinatlon of a top followerplate, a frictionpost depending centrally from said plate, said Dostbeing tapered at its lowered end, a pair of friction shoes on oppositesides of the post, each shoe having a laterally extending platformmember projecting toward and beyond the other shoe, and each shoe beingconnected by spaced apart webs with its platform member, the said webshaving rounded bearing portions below the planes of said platformmembers to provide for the rocking movement of the shoe toward and awayfrom the post, spring means surrounding said post and shoes and bearingat its opposite ends on the follower plate and the platform members tooppose the rocking movement of said shoes, a base plate below theplatform members having bearing depressions for the rounded bearingportions of said webs and having an upstanding boss positioned betweensaid bearing portions to prevent lateral displacement of said bearingportions with respect to said base plate.

3. In a friction shock absorber, the combination of a supporting baseplate having an upstanding central boss forming spaced apart verticalshoulders and fulcrum beanng depressions adjacent said shoulders, a pairof friction shoes each comprising friction portions and spaced apartwebs extending downwardly and having bearing portions supported forrocking movement in said bearing depressions of said base plate, thewebs of one shoe being positioned be tween the spaced apart webs 'of theother shoe, laterally projecting platform segments connected to the websof each shoe, a tapered friction post positioned between said frictionportions of the shoes and movable in a lengthwise direction with respectthereto, said post having a lateral flange at its upper end and a coilspring surrounding said post and shoes and bearing at its opposite endson said lateral flange and said platform segments.

4. In a friction shock absorber, the combination of a supporting baseplate having an upstanding central boss forming spaced apart verapartwebs extending downwardly and having bearing portions supported forrocking movement in said bearing depressions of said base plate, thewebs of one shoe being positioned between the spaced apart webs of theother shoe, laterally projecting platform segments connected to the websof each shoe, a tapered friction post positioned between said friction prtions of the shoes and movable in a 1engthwise direction with respectthereto, said post having a lateral flange at its upper end and a coilspring surrounding said post and shoes and bearing at its opposite endson said lateral flange and said platform segments, and an assembly pinextending through the boss of said base plate and the webs of saidshoes.

WILLIAM A. GEIGER.

